Humidity Sensor
www.vishay.com
For technical questions contact: nlr.europe@vishay.com
Document Number: 29001
66
Revision: 10-Oct-03
2322 691 90001
Vishay BCcomponents
APPLICATIONS
Humidity measurements in electronic hygrometers for
domestic use
Self-regulating air humidifiers, etc.
QUICK REFERENCE DATA
Note
Unless otherwise stated, measurements are in accordance with
"IEC publication 60539"
.
Stability is in accordance with
"CECC 43000"
and
"IEC 60068-2"
.
PARAMETER
VALUE
UNIT
Humidity range (RH)
10 to 90
%
Capacitance at +25
C; 43% RH; 100 kHz
122
15%
PF
Tan
at +25
C; 100 kHz; 43% RH
0.035
Sensitivity between 12 and 75% RH
0.4
0.05
PF/%R
Frequency
1 to 1000
kHz
Temperature dependence
0.1
%RH/K
Response time in minutes
(to 90% of indicated RH change at
+25
C, in circulating air):
between 10 and 43% RH
<
3
between 43 and 90% RH
<
5
Hysteresis (for RH excursion of
10 to 90 to 10%)
3
%
Maximum AC or DC voltage
15
V
Storage humidity range (RH)
0 to 100
%
Ambient temperature range:
operating
0 to +85
C
storage
-
25 to +8
C
Drop test:
height of free fall
1
M
Mass
1.3
G
DESCRIPTION
This capacitive atmospheric humidity sensor consists of a
non-conductive foil, which is covered on both sides with a
layer of gold. The dielectric constant of the foil changes as a
function of the relative humidity of the ambient atmosphere
and, accordingly, the capacitance value of the sensor is a
measure for relative humidity. The foil is clamped between
contact springs and assembled in a plastic housing. It is
provided with two connecting pins which fit printed-circuit
boards with a grid pitch of 2.54 mm, provision is also made
for fastening with 3 mm bolts. The characteristics are not
affected by incidental water condensation on the sensor foil.
It should not be exposed to either acetone or chlorine
vapours.
MOUNTING
The device can be soldered directly on to a printed-circuit
board or fastened with 3 mm bolts.
SOLDERING
Solderability:
240
C;
4 s.
Resistance to heat:
240
C;
4 s.
ROBUSTNESS OF TERMINATIONS
Tensile strength: 10 N.
DIMENSIONS
in millimeters
ELECTRICAL CHARACTERISTICS
MBD125
5.0 0.5
3.1 0.1
11.5
0.5
17.0
0.5
5.08
1.15 max
3
23.0
0.5
15.5 0.5
Component outline.
0
100
150
110
MEA832
120
130
140
50
C
(pF)
RH (%)
Typical capacitance as a function of relative humidity.
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